Mapping nitrogen loading in freshwater systems

The South African Scoring System (SASS5) is a well-used bio monitoring tool for the assessment of anthropogenic inputs and ecosystem health in freshwater systems.

Increased anthropogenic inputs have numerous effects in aquatic ecosystems, including the facilitation of invasive weeds.

There is however a number of ecological challenges associated with SASS5 application, with the primary drawback being that SASS5 scores only provide red flags after ecosystem degradation has taken place.

Recent work has shown that the stable isotope values of the Duckweed (Spirodela sp.) can clearly track different species and concentrations of nitrogen loading in laboratory setting.

This project aims to field test this technique as bio-monitoring tool in freshwater systems.